1. Area of the Art
The invention relates generally to vessel handling mechanisms for automated chemical analyzers, and specifically to bulk vessel feeders for automated chemical analyzers.
2. Description of the Prior Art
Automated chemical analyzers are widely used in clinical chemistry sampling and analyzing applications, and are often involved in the supplying of bulk vessels for performing various assays. The basic functions of a mechanism for supplying bulk vessels often involve feeding and sorting the vessels for processing and analyzing by the automated chemical analyzers.
The following references are found to be pertinent to the field of the present invention:
U.S. Pat. No. 4,944,382, issued to Gradoboev et al on Jul. 31, 1990, disclosed an apparatus for orienting parts in feeding devices of various units. The apparatus includes a screw conveyor and members for picking up improperly oriented parts and means for reorienting parts.
U.S. Pat. No. 5,314,072, issued to Frankel et al. on May 24, 1994, disclosed a method of detecting whether bottles for recycling contain chlorine. The method includes the steps of sensing whether the bottles are clear and/or colored, and the step of irradiating the bottles with X-rays to detect the presence of chlorine. It further includes the step of emitting and passing circularly polarized light through the bottles for determining the composition of the bottles.
U.S. Pat. No. 5,439,093, issued to Drewitz on Aug. 8, 1995, disclosed an apparatus for unscrambling a population of containers. The apparatus includes a plurality of container handling stations between an in-feed station or guide and an output station, each having two container engaging members and a rotating means for rotating the container engaging members to alter the orientation of the containers.
U.S. Pat. No. 4,634,575, issued to Kawakami et al. on Jan. 6, 1987, disclosed an automatic cuvette loading apparatus for supplying cuvettes contained in magazines one by one into successive recesses of a cuvette holding turntable. The apparatus includes a plurality of magazines and means for feeding the magazines into a cuvette loading position.
U.S. Pat. No. 4,832,175, issued to MacIntyre on May 23, 1989, disclosed a sorting and orienting structure. The structure includes an annular sorting and orienting table and a drive shaft for rotating the table to sort and orient work pieces.
U.S. Pat. No. 5,065,852, issued to Marti on Nov. 19, 1991, disclosed a machine for automatically positioning and feeding bottles. The machine includes two hoppers (a main hopper and a receiving hopper), a container holder support means supported below the main hopper, and means for driving the container holder support means along a path adjacent to a peripheral portion of the bottom of the main hopper.
U.S. Pat. No. 5,143,506, issued to Sticht on Sep. 1, 1992, disclosed an apparatus for aligning and sorting disordered parts. The apparatus includes two conveyors, including an elevator conveyor and a linear sorting conveyor.
U.S. Pat. No. 5,186,307, issued to Doudement et al. on Feb. 16, 1993, disclosed a transport device for removing interlocked preforms used in manufacturing synthetic bottles. The device includes a conveyor track incorporating two substantial parallel slide-rails.
U.S. Pat. No. 5,443,149, issued to Rohwetter et al on Aug. 22, 1995, disclosed an apparatus for aligning parts supplied in a disordered fashion. The apparatus includes a rotatable drum having a bottom made of at least two substantially coaxial discs arranged one above the other.
U.S. Pat. No. 5,582,796, issued to Glen A. Carey et al. on Dec. 10, 1996, disclosed a feed and orientation mechanism in an automated analyzer. The mechanism includes an orientation chute as a means for orienting a cuvette. The orientation chute has a pair of upper parallel slide surfaces which are separated by a slot which has a longitudinal sliding axis for receiving the cuvette from the conveyor belt at the first point so that the flanges of the cuvette are parallel with the longitudinal axis of the slot and are supported on said slide surfaces. The cuvette extends downwardly in the slot to enable the cuvette to slide downwardly on the chute along the axis from the first point to the second point.
Other references also found to be of interest to the field of the present invention include: U.S. Pat. No. 1,311,590 issued to Bingham on Jul. 29, 1919; U.S. Pat. No. 1,653,480 issued to Soubier on Dec. 20, 1927; U.S. Pat. No. 2,341,265 issued to Crawford on Feb. 8, 1944; U.S. Pat. No. 2,734,627 issued to Shields on Feb. 14, 1956; U.S. Pat. No. 2,936,059 issued to Hakogi on May 10, 1960; U.S. Pat. No. 2,954,862 issued to Clark on Oct. 4, 1960; U.S. Pat. No. 2,987,180 issued to Shields on Jun. 6, 1961; U.S. Pat. No. 3,119,487 issued to Wyle et al. on Jan. 28, 1964; U.S. Pat. No. 3,221,857 issued to Keller on Dec. 7, 1965; U.S. Pat. No. 3,276,566 issued to Raasch on Oct. 4, 1966; U.S. Pat. No. 3,338,373 issued to Aidlin et al. on Aug. 29, 1967; U.S. Pat. No. 3,372,310 issued to Kantor on Mar. 5, 1968; U.S. Pat. No. 3,537,567 issued to Nowicki on Nov. 3, 1970; U.S. Pat. No. 3,633,730 issued to Deutschbein on Jan. 11, 1972; U.S. Pat. No. 4,244,459 issued to Garrett on Jan. 13, 1981; and U.S. Pat. No. 4,681,230 issued to Kupper on Jul. 21, 1987. These references are generally related to the field of container handling technology.
While many cited references have disclosed mechanisms for handling bulk vessels, they all have certain limitations and therefore cannot satisfy the needs addressed by the present invention. For example, some prior mechanisms are designed to handle rectangular shaped cuvettes with planar flanges but not circular shaped vessels. In addition, many prior mechanisms utilize an inclined sliding chute for sorting the vessels. Furthermore, many prior mechanisms are not designed to feed vessels to a carriage module that moves randomly.
Bulk vessels are preferred in many automated chemical analyzers because bulk vessels are less costly than vessels with packaging for a vessel handler. Bulk vessels can also be stored economically and require minimal instrument space for vessel storage and vessel feeding apparatus. In addition, handling bulk vessels requires minimum operator training and reduces the problems caused by human errors.
Therefore, it is desirable to provide a new system for feeding and sorting bulk vessels for an automated chemical analyzer.
It is an object of the present invention to provide a system for sorting and feeding bulk vessels to an automated chemical analyzer.
The objects and advantages of the present invention are achieved in a bulk vessel feeder of the present invention by having a sorting and orienting mechanism, intercepting the vessels and ejecting them into a guide, while sorting and orienting the vessels such that they are all headed by their closed ends when traveling in the guide.
In accordance with embodiments of the present invention, the bulk vessel feeder has a frame structure with two upright side plates connected in a spaced-apart parallel relationship. An elevator chain driven by a drive sprocket is supported between the two side plates and carries a series of scoopers. Each scooper is configured to carry at least one vessel in a horizontal orientation. The bulk vessel feeder has a sorting and orienting mechanism mounted on the frame structure at a location intercepting the vessels carried by the scoopers. The sorting and orienting mechanism includes a first ram for engaging the closed end of the vessels carried by the scoopers, if the closed ends of the vessels are facing the first ram, and ejecting such vessels one at a time from the scoopers into a first passage way with their open end headed into the first passage way first. The sorting and orienting mechanism also has a second ram for engaging the open end of the vessels carried by the scoopers, if the open ends of the vessels are facing the second ram, and ejecting such vessels one at a time from the scoopers into the second passageway with their closed end headed into the second passageway first. Both passageways feed into a guide that leads to an escape mechanism, which dispenses the vessels one at a time to an automated chemical analyzer.
Such an arrangement has been found to provide a number of advantages. As explained in greater detail below, it has been found that the bulk vessel feeder of the present invention provides the features of feeding and sorting of circular shaped vessel to a carriage module that makes random moves. It also utilizes open-and-closed end features for sorting vessels, which is more robust than solely relying on gravity force because the vessels have minimal mass.
Another important feature of the bulk vessel feeder of the present invention is that it utilizes a controllable actuator to forcibly move the vessels during orientation, which reduces the susceptibility of vessel jamming due to electrostatic charge buildup on the vessels. In addition, the bulk vessel feeder of the present invention employs large scoopers for sweeping a large horizontal-plan area in the hopper in conjunction with the staging section in the hopper that pre-orients the vessels to produce a high yield of proper oriented vessels in the scoopers. Furthermore, the angling of the track of the bulk vessel feeder of the present invention permits the excess vessels to be dispensed back into the hopper in a preferred orientation. Similarly, the reciprocating escapement of the vessel feeder delivers vessels on demand to the shuttle module. Overall, the bulk vessel feeder of the present invention has a very compact design which delivers vessels at a high throughput and can be adapted to a variety of vessel shapes.
The bulk vessel feeder of the present invention is well suited for use in conjunction with an automated chemical analyzer, such as, but not limited to, Access Nexgen (Beckman Coulter Inc., CA).
The invention is defined in its fullest scope in the appended claims and is described below in its preferred embodiments.